Current in a Battery: Solving w/ Kirchoff's Law

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SUMMARY

The discussion focuses on calculating the current in a battery system using Kirchhoff's Law. Given a voltage (V) of 5.5 V and a resistance (R) of 0.50 ohms, the initial approach using the formula I=V/R yielded incorrect results. The correct method involves applying Kirchhoff's current law, which states that the total current entering a junction equals the total current leaving, leading to the conclusion that the current of the starter is approximately 170-171 A. The user struggled with multiple techniques but ultimately required a structured approach to solve for the unknown currents I1, I2, and I3.

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Homework Statement


A dead battery is charged by connecting it to the live battery of another car with jumper cables. Assume that V = 5.5 V and R = 0.50 .

What is the current of the starter and the current of the dead battery?


Homework Equations


I=V/R, I1=I2+I3, basically Kirchoff's law...



The Attempt at a Solution


I thought for finding the current of the starter all, you had to do was use I=V/R, so it would 5.5/.50, but it came out wrong :(. I then tried multiplying the two resistances together..still no luck, and did V/R..still no luck, however I found that the answer comes out to be 170-171, and how I have no idea how to get that. I also tried finding the current and then subtracting it from the intial voltage and divide by the intial resistance..when I did that, I got somewhere in the 100's, but no where near the answer. I came up with millions of techniques, but none worked. Can someone help? I'm really stuck on this.

DIAGRAM BELOW FOR REFERENCE..
 

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You've got 3 unknowns, which are I_1, I_2, I_3

Now search 3 equations that can solve your unknowns.
 

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